Conventional Cages Research Articles

Effect of A New Housing System on Skin Lesions, Performance and Soiling of Fattening Rabbits: A German Case Study.

Simple SummaryThe present study evaluated a new housing system for fattening rabbits which, on the one hand, complied with new German legal requirements and on the other hand was expected to provide some benefits in terms of animal welfare compared to previously established cage systems in Germany. Fattening rabbits kept in the new housing system showed a lower incidence of injuries and higher daily weight gain than rabbits kept in conventional cages on the same farm, which may indicate increased welfare in this regard. However, an increased mortality rate and hygienic challenges posed by the new system may indicate impaired welfare and are not acceptable in this form. Finally, both the conventional and the new system were deficient in terms of animal welfare. Further research is necessary to find a housing system that complies with German legislation and keeps rabbits in good health and welfare simultaneously.The aim of the present study was to develop and evaluate a new housing system for fattening rabbits. Data were collected on a farm with rabbits housed either under new conditions (NC) or established (conventional) conditions (CC). NC housing was characterized by large groups (Ø 58 rabbits, max. 12 rabbits/m2), slatted plastic floor (11 mm slats and 11 mm gaps), elevated platforms with partly solid floor, boxes and different enrichment materials. CC rabbits were kept in small groups (eight rabbits, 23 rabbits/m2) in cages with wire-mesh floor, an elevated platform, a box and one gnawing stick. Skin lesions and weight gain of 524 rabbits, cleanliness of their hind feet as well as their mortality and morbidity were investigated from weaning to slaughter in five batches. The evaluations showed higher daily weight gain (46.3 ± 6.0 g vs. 43.1 ± 5.5 g) and final weight (2878 ± 328 g vs. 2707 ± 299 g), as well as a lower cumulative lesion score at the middle of the fattening period in NC than in CC rabbits. Nevertheless, cleanliness of hind feet was assessed to be worse and mortality was higher in the NC housing. The NC system provided some benefits in terms of animal welfare compared to the conventional system, but hygienic challenges posed by this system make further adjustment necessary.

The effect of beak tissue sloughing and post-treatment beak shape on the productivity of infrared beak-treated layer pullets and hens.

Infrared beak treatment (IRBT) results in a change in beak shape; however, it is unclear what effect variations in post-treatment beak shape have on young pullets. Additionally, the impact of sloughing of the treated beak tissue is not fully understood. Two experiments were conducted to determine the effects of beak tissue sloughing and post-treatment beak shape on the productivity of infrared beak-treated Lohmann Brown (LB) and Lohmann LSL-Lite (LW) pullets and hens. Birds were treated on day of hatch and IRBT equipment settings were adjusted to create 4 specific beak shapes: shovel (SHV), step (STP), standard (STAN), and an untreated sham control (C). Experiment 1 pullets (n = 160) were housed in cages from 1 to 29 d of age and had access to water through chick founts or 360° nipple drinkers (2 replicate cages per treatment). Data collected included body weight (BW), feed intake (FI), feed efficiency (FE), and water disappearance (WD). Experiment 2 pullets (n = 640) were housed in floor pens from 1 d to 18 wk of age (2 replicate pens per treatment) then conventional cages during the laying period (6 replicate cages per treatment). Data collected included BW, FI, egg production, and egg quality. Data were analyzed using PROC MIXED (SAS® 9.4) and differences were significant when P ≤ 0.05. During early life, the IRBT treatments and sloughing had minor effects on FI, FE, and BW. At 4 wk of age, STAN pullets were lighter than C pullets; however, differences were no longer apparent after this age. Pullets with STP or STAN beak shapes had lower WD than C pullets when allowed access to water via nipple drinkers but this did not result in reduced growth. Throughout the laying period, SHV hens laid more saleable eggs than C hens, with no other effects on production. Overall, variations in beak shape and sloughing of the beak tissue had minimal impacts on the productivity of LW and LB pullets and hens.

Laying hen production and welfare in enriched colony cages at different stocking densities.

Many laying hen companies in the United States are pledging to move away from intensive conventional cages to extensive housing systems. Enriched colony cages (ECC) are a practical alternative to conventional cage systems. Scientific research is limited on the effects of ECC on hen production and welfare. Therefore, the objective of this study was to evaluate the effects of stocking density on welfare and performance with the overall outcome to provide guidance on stocking density for ECC. At 16 wk, W-36 pullets were placed into 2 commercial ECC housing systems. Within each ECC enclosure, hens were allocated into 1 of 6 stocking densities: A) 465 to 484 cm2/bird, B) 581 to 606 cm2/bird, C) 652 to 677 cm2/bird, D) 754 to 780 cm2/bird, E) 799 to 832 cm2/bird, and F) 923 to 955 cm2/bird. Body weight, egg production, mortality, and Welfare Quality data were collected each 28 d period from 17 to 68 wk. The 6 ECC stocking densities had several transient effects on production measures within age periods with no difference in hen-day production (P > 0.05). Body weight was affected by stocking density (P < 0.05) where hens raised at stocking density A (465 to 484 cm2/bird) weighed at least 25g less than hens from other stocking densities. Stocking density differences for Welfare Quality assessments were only apparent for feather coverage. Hens raised at stocking density A (465 to 484 cm2) consistently had the poorest (P < 0.05) crop, keel, belly, back, and rump feather coverage. The keel, neck, and back body regions had poorer feather coverage when hens were raised at stocking densities B (581 to 606 cm2) and C (652 to 677 cm2) compared to hens from lower stocking densities (P < 0.05). Therefore, the minimum area per hen housed in commercial ECC systems should be 754 cm2 per bird for greater feather coverage.

Influence of nest boxes and claw abrasive devices on feather pecking and the fear responses of layer breeders in natural mating colony cages

Natural mating colony cages for parent-stock layer breeders, instead of conventional cages with artificial insemination, have been widely adopted by many commercial farms in China. Although some natural mating behaviours can be expressed and broader activity space is provided compared with that of conventional artificial insemination cages, the environment is still relatively barren. The aim of this study was to investigate the effects of providing nest boxes and claw abrasive devices (CADs) in this colony cage system on feather pecking (FP), feather condition, fear and physiological stress in layer breeders. Twelve treatments were compared in a factorial arrangement, including 2 types of nests (large and small), 3 types of CADs (abrasive strips, rubber mat with grooves, and metal plates with holes), and the control (without the provision of nests and CADs). Nine cages per treatment were involved, with 10 roosters and 90 hens per cage. The results showed that the nests had a significant effect (P ≤ 0.05) on the frequency of severe feather pecking (SFP); environmental pecking (ENP); food pecking (FOP); back, rump, and belly coverage condition; tonic immobility (TI) duration; avoidance distance (AD); and corticosterone and 5-HT concentrations. Except for the blood parameters, the CADs had a significant effect (P ≤ 0.05) on the frequency of SFP and FOP; back, rump, tail coverage condition; duration and latency of TI test; hens’ novel object (NO) recognition score; and distance in the AD test. In addition, significant nest × CAD interactions (P ≤ 0.05) were noted for SFP, ENP, and FOP; back, rump, and tail coverage condition; duration in the TI test; hens’ novel object (NO) recognition score; distance in the AD test; and the concentration of corticosterone. Mortality was significantly (P ≤ 0.05) reduced by nests, CADs and their interaction. It was concluded that the nests and CADs that were equipped in our study could be regarded as rewarding environmental necessities that could alleviate FP activities, improve feather coverage condition, and reduce stress levels and mortality rates. Large nests and abrasive strips were the preferred choice over colony cages without nests and CADs.

Housing Rabbit Does in a Combi System with Removable Walls: Effect on Behaviour and Reproductive Performance

Simple SummaryThis study focuses on the welfare and reproductive performance of rabbit does housed in individual conventional cages (C) or in different colony cages: simple (does in the group for 100% of the reproductive cycle: C1) or combi (in both individual and group caging: C2). The results showed that C2 had some benefits compared to continuous grouphousing, but both colony systems achieved lower reproductive performance levels than the conventional system. Although C2 showed some improvement on the behaviour of does, the aggressiveness of group-housing the does to establish a rank order was responsible for injuries, higher disease risks, and higher kit mortality.We evaluated the effects of two types of colony cages, in which rabbit does were always in a group (C1), and where they were in combi cages furnished with removable internal walls to allow both individual and grouphousing (C2), in addition to the control group (C: conventional individual cage), on welfare, reproductive performance, and global efficiency. Forty-eight New Zealand White nulliparous rabbit does underwent artificially insemination (AI) and were divided into three groups, and reared in the different systems for about 1 year. The reproductive rhythm provides AIs at weaning (30d). In the C1 system, does were continuously grouped, while in C2, walls were inserted four days before kindling and removed 1week after it (60% of the timesheet in group). Reproductive traits and behaviour were evaluated during the entire year. The behavioural observations were performed around days 7, 36, and 44, corresponding to the inclusion of the does in the maternal cages, the insertion of walls four days before kindling, and the removal of the walls 1week after parturition in the C2 group, respectively. The percentages of does with severe skin injuries and the distribution of the injuries on different parts of body were also registered. Does reared in conventional cages showed the greatest presence of stereotype behaviours, while the C1 group showed the highest (p < 0.05) incidence of aggressiveness after regrouping (attack, dominance features, and lower allo-grooming) in comparison to the C2 group (17% and 22%, in C2 and C1 does, respectively).Individually caged does achieved the best productive performance (sexual receptivity, fertility, kindling rate, and number of kits born alive and at weaning). The C1 group showed the lowest performance (p < 0.05), whereas C2 showed an intermediate one. Does housed in the combi cage (C2) had higher (p < 0.05) receptivity and fertility rates and higher numbers of kits born alive and at weaning (79.2% and 76.2%; 7.95 and 7.20, respectively) than the C1 group, but lower values (p < 0.05) than does that were individually housed.

Modification of perchery system: Preference for ramps rather than ladders during early adaptation period for cage-reared pullets

Poor early adaptation in aviaries has adverse effects on welfare and the later production. Effects of system modification by ramps and ladders on early adaptation of birds were investigated. A total of 240 pullets and 24 cockerels of Yukou Jing Pink II parent stock were allocated into six perchery compartments at the age of 83 days from conventional cages. Three compartments were modified with ramps of different angles, 30°, 40° and 30° & 50° combination. The other compartments were fitted with 2 ladders, with 22 cm steps and 33 cm steps. Spatial distribution of birds and eggs, as well as the data of ramps and ladders utilization were used to assess birds’ adaptation and the effectiveness of modification facilities. A higher proportion of hens got onto the tiered platforms in ramp group (p<0.001) and engaged in feeding (p=0.002). Inversely more than 85.0% of hens dwelled on the system floor in the ladder group for the whole observation period. The proportion of birds feeding increased over time (p<0.001), with the proportion of birds lying decreasing (p<0.001). A higher frequency of utilization of ramps was found compared with ladders (4.5-25.8 vs. 2.8-14.7 times/40 birds per hour). For ramp use, 79.3% of hens negotiated level change by using 30° ramp and behavioral process was also found related with the type of ramps. On the contrary, very few successful level changes were observed via ladders and 60% of ladder use was ended with birds backing to the system floor. Besides, a higher proportion of non-nest eggs was recorded in ladder group in the early laying period. These results indicated that modification of ramps is more applicable for improving birds’ early adaptation and later production in perchery system of multi-tier, especially for pullets reared in conventional cages. Keywords: animal welfare, modification, perchery system, adaptation, pullet, ramp, enriched cage system DOI: 10.25165/j.ijabe.20191204.4030 Citation: Zheng H Y, Li B M, Tong Q, Chen G, Li X Y. Modification of perchery system: Preference for ramps rather than ladders during early adaptation period for cage-reared pullets. Int J Agric & Biol Eng, 2019; 12(4): 34–42.

Hen housing system information effects on U.S. egg demand

The U.S. egg industry has been moving rapidly towards “cage-free” aviary housing as an alternative to conventional cages for hens. A choice experiment was used to evaluate the U.S. public’s willingness to pay (WTP) for egg attributes including housing system, color, size, and certifying agency. A significant difference in WTP for hen housing systems was found using video information treatments describing hen housing systems. When respondents were shown videos of egg production systems, they were indifferent between cage-free aviary and the alternative enriched colony hen housing system whereas with no video information the respondents clearly preferred the cage-free system. Results point towards potential public misunderstanding of the costs and benefits associated with the “cage-free” egg label designation and highlight potential discrepancies between industry commitments and informed consumer preferences.

Development of a Scoring System to Assess Feather Damage in Canadian Laying Hen Flocks.

Simple SummaryFeather damage is a continuous welfare challenge in the management of egg-laying hens. Canada is currently transitioning from conventional cages to alternative housing systems, where the risk of feather damage may increase due to larger group sizes. This change increases the need for continued and reliable assessment of flock feather condition, for which Canada does not have a standard method. Within this study, a feather damage scoring system and visual scoring guide were developed, with the ultimate goal of streamlining and increasing plumage assessment of laying flocks by farmers on Canadian commercial farms. Two differing feather scoring systems (LayWel and AssureWel) were compared based on user-friendliness and reliability. The AssureWel scoring system was easiest to use and achieved the most consistent outcomes among scorers for the back area of the body. This informed the design of a modified version with scoring levels from 0 to 2 for a sample of 50 birds per flock, along with an informational, visual guide for farmers. Training of farmers to use this simplified scoring system under commercial conditions can provide a benchmarking tool for feather damage levels, as well as a way to measure the success of management strategies to prevent and control feather damage.Feather damage (FD) due to feather pecking behavior is an ongoing welfare concern among commercial egg-laying hens. Canada’s current transition from conventional cage housing to alternative housing systems, where FD can spread easily within large flocks, underlines the need for frequent and accurate assessment of plumage condition. A standardized methodology for assessing FD in Canada does not yet exist. To improve FD assessment on commercial farms, a FD scoring system and visual scoring guide for farmers were developed. Two existing plumage scoring systems, LayWel and AssureWel, which differ in level of detail and bird handling, were assessed for ease of use, and intra- and inter-observer reliability. Practical application of the AssureWel scoring system was greatest, with strong intra- and inter-observer reliability for the back region of the body (weighted kappa = 0.88 for both measures) in small-scale flocks. This informed the creation of a modified version of the AssureWel system, which included three scoring levels and the visual assessment of 50 birds per flock. An accompanying guide was developed including sampling instructions and depictions of the scoring scheme, both written and visual. This simplified scoring system can serve as a benchmarking tool for FD prevalence, and can allow for future effectiveness assessments of management strategies to prevent and control FD; however, farmers should be trained to apply this system under commercial conditions.

Effects of rearing and adult laying housing systems on medullary, pneumatic and radius bone attributes in 73-wk old Lohmann LSL lite hens

We determine interactive effect of a combined model of housing systems for rearing pullets and raising adult birds on bone quality. The LSL-Lite pullets were reared in either an aviary system (A) or conventional cages (C). At week 16, the birds were transferred either to the same housing type through the adult stage (A-A or C-C, for rearing and adult phase, respectively) or to enriched system (A-E or C-E, respectively). In the rearing stage, C cages housed 16 pullets/cage (week 0 to 6) and 8 pullets/cage (week 6 to 16) with a space allowance of 145 and 290 cm2/pullet, respectively; the rearing aviary housed 756 pullets/enclosure allowing 285 cm2/pullet (week 0 to 6) and 754 cm2/pullet (week 6 to 16). In the adult phase, C cages were 58.4cm wide × 66.0cm deep (482 cm2/pullet, 8 pullets/cage). For adult A, a commercial multi-tier aviary provided a space allowance >1000 cm2/hen system with litter area. Enriched system housed 60 birds/cage at 750 cm2/bird with perches, nest, and scratch mat. Bone samples were collected from the adult phase (week 73) and analysed for bone quality indices including bone breaking strength (BBS), total bone weight (TBW), ash content of the medullary (femur and tibia), pneumatic (humerus and keel), and radius bones. The A-A hens had the greatest (P < 0.05) TBW for medullary (femur and tibia) and pneumatic (humerus and keel) bones compared with hens from other housing models with exception of C-E hens. In addition, ash content was heavier (P = 0.048) for both A-A and C-E managed birds compared to the other housing. Birds in C-C system had the least score (P < 0.05) for TBW and ash content in all bone types. Regardless of the housing system, BBS was correlated (r = 0.60; P < 0.01) with the amount of ash and TBW, particularly for humerus and tibia. The results provide an insight on the impact of type of housing system in rearing and production stages on late cycle bone quality.

Comparison of chemical composition of eggs from laying hens housed in different production facilities: a market study

Eggs as a part of human diet dates to the prehistoric period. After the domestication of Gallus species, Gallus gallus domesticus and their eggs spread across the globe. Eggs proved to be one of the best and affordable sources of nutritionally important components in human diet, such as proteins, vitamins, lipids and some dietary significant elements. Progress in egg production methods, in European union, is recently mostly focused on the improvements in the field of welfare of laying hens, which is part of the plan set by European union council directive 1999/74/EC. Nowadays there are 4 main egg production systems divided by the way of keeping laying hens - Enriched cage, Free range, Barn and Organic. The aim of this study was to evaluate the impact of different hens housing systems on elemental (Ca, K, Mg, Na, P, Ca, K, Zn), total protein and lipid composition of whole eggs, yolk and albumen. Elemental analysis was performed by ICP-OES, total lipid content by Kjehldahl method and total lipids by Soxhlet extraction. Differences in whole egg were found in 8 from 9 tested parameters - K, Mg, Ba, Fe, P, Zn, total lipids and proteins. Assessment of the differences were done by ANOVA and Tukey`s test. Production systems were also successfully differentiated by principal component analysis. It was found that eggs from alternative production systems did not exhibit higher nutritional value than eggs from conventional cage facilities. In the case of total protein, conventional eggs contained highest average amount. It was also evident, that impact on chemical composition is difficult to assign to production system in general, which was confirmed by alternative studies from this field, which in many cases considerably differs.&#x0D;

Carbon-fibre cage reconstruction in anterior cervical corpectomy for multilevel cervical spondylosis: mid-term outcomes.

Mid-term clinical and radiological evaluation of a carbon-fiber cage in multilevel cervical spondylosis (MCS). Anterior cervical corpectomy and fusion (ACCF) using titanium mesh cages (TMC) has shown satisfactory outcomes, but with subsidence of up to 20%. Conventional long-fiber carbon fiber cages have shown a safe profile in discectomy/fusion (ACDF) but with minimal data in the setting of corpectomy. Retrospective review of a single centre multi-surgeon cohort of MCS patients from 2007-2012. Follow-up period was a minimum of 3.5 years, mean 6 years. Outcomes included peri-operative, clinical [Nurick, European Myelopathy, Visual Analogue Scores (VAS), modified Japanese Orthopaedic Association (mJOA) scores and radiographic (C2C7, Cobb & ROM angles)]. A total of 102 consecutive patients were included. Mean length of stay was 5.5 (SD 3.5) days, blood loss 322 (SD 358) mL and operative time 98 (SD 31) min. Corpectomy levels included 72 single-level ACCF and 30 multiple ACCF. Fourteen had peri-operative complications. Three patients required early cage revisions. Mean pain scores improved from VAS neck 4.6 to 2.6 (P<0.01) and VAS arm 5.1 to 2.0 (P<0.01). Mean Nurick score improved from 1.2 to 0.4/4 (P<0.01). Mean follow-up EMS was 15.9/18 and mJOA was 14.0/17. Seventy follow-up radiographs were obtained. Flexion-extension angulation differences of >3 mm across the instrumented level were present in 5 patients, all of which displayed fusion of either grade 1 or 2. 7 had C2C7 kyphosis. Severe subsidence (>3 mm) was seen in 9 cases (13%). Mid-term outcomes of this carbon-fiber cage indicate that it is safe and durable for the treatment of MCS with a similar radiological profile to that of TMC.

Development of a time projection chamber with a sheet-resistor field cage

A new-concept time projection chamber (TPC) using a commercial resistive sheet, sheet-resistor micro-TPC SR-microPIC, was developed and its performance was measured. SR-microTPC has the potential to create a more uniform electric field than conventional TPCs with resistor-chains owing to its continuous sheet resistivity, and its production would be easier than that of conventional TPCs. The material used in this study, Achilles-Vynilas, was found to be thin, transparent, and low-radioactive. The performance test with cosmic muons showed very promising results, including the demonstration of a good tracking-performance. This type of TPC field cage can offer an alternative for the widely used conventional field cages

Effects of New Cage Profiles on the Improvement in Biomechanical Performance of Multilevel Anterior Cervical Corpectomy and Fusion: A Finite Element Analysis

For multilevel cervical fusion, anterior corpectomy and fusion (ACCF) induces more implant-related complications than anterior diskectomy and fusion (ACDF), which implies that the biomechanical stability of ACCF may be insufficient. The aim of this study was to assess whether the optimization of the cage profiles could improve the biomechanical performance of multilevel ACCF. Three finite element models were constructed and compared, including 3-level ACDF, 2-level ACCF using a conventional cage for reconstruction, and 2-level ACCF using a new cage for reconstruction. The ends of the new cage possessed additional end rings and emulated the end plate geometries. The ranges of motion (ROMs) of the surgical segments and the stress peaks in the end plate, fixation system, and screw-bone interface were compared. Compared with preoperative status, ACDF and ACCF reduced the segmental ROMs by 96.1%-98.2%. The end plate stress peaks were the highest in ACCF using the conventional cage (10.1-18.6 MPa), followed by ACCF using the new cage (7.7-14.3 MPa) and ACDF (5.3-9.1 MPa). ACDF induced the highest stress peaks in the fixation system and screw-bone interface (32.5-39.3 MPa and 12.1-12.7 MPa, respectively), followed by ACCF using the conventional cage (20.4-31.7 MPa and 10.3-13.6 MPa, respectively) and ACCF using the new cage (18.6-25.7 MPa and 9.7-12.6 MPa, respectively). The application of the new cage decreased the risks of cage subsidence and instrument-related complications in multilevel ACCF. Under the condition where cage subsidence was prevented, ACCF was superior to ACDF in terms of construct stability and avoiding instrument-related complications.

First Operation of a Resistive Shell Liquid Argon Time Projection Chamber: A New Approach to Electric-Field Shaping

We present a new technology for the shaping of the electric field in Time Projection Chambers (TPCs) using a carbon-loaded polyimide foil. This technology allows for the minimisation of passive material near the active volume of the TPC and, thus, is capable to reduce background events originating from radioactive decays or scattering on the material itself. Furthermore, the high and continuous electric resistivity of the foil limits the power dissipation per unit area and minimizes the risks of damages in the case of an electric field breakdown. Replacing the conventional field cage with a resistive plastic film structure called “shell” decreases the number of components within the TPC and, therefore, reduces the potential points of failure when operating the detector. A prototype liquid argon (LAr) TPC with such a resistive shell and with a cathode made of the same material was successfully tested for long-term operation with electric field values up to 1.6 k V cm − 1 . The experiment shows that it is feasible to successfully produce and shape the electric field in liquefied noble-gas detectors with this new technology.

Health of Commercial Egg Laying Chickens in Different Housing Systems.

To determine which type of egg-laying hen housing was best for the chickens, the workers in those housing systems, the environment, and society based on food safety and affordability, a combined research project involving egg suppliers, food manufacturers, food service representatives, and food retailers, as well as research institutions and nongovernmental organizations, was performed. This study reports the hen health and welfare portion based upon veterinary health inspections and compared mortality rates, skeletal abnormalities, causes of death determined by necropsy, and titers to infectious bronchitis and Newcastle disease viruses. Birds were housed on a preexisting Midwest layer complex, which consisted of conventional cages (CC). New houses were built adjacent to the CC house where enriched colony cages (EC) and an aviary system (AV) were installed. Two flock cycles from housing to 78 wk of age were followed. Total mortality was greatest for AV, while CC and EC birds were similar. Keel bone fractures were greatest for AV, next greatest for EC, and least for CC birds. Other skeletal abnormalities were greatest for AV birds. Birds dying from being caught in the structure, pick out, and persecution was most frequent for AV and next most frequent for EC, but nonexistent with CC birds. Infectious pododermatitis (bumblefoot) was most frequent for AV, next most frequent for EC, and essentially nonexistent for CC birds. There was little to no effect on antibody titers based upon housing type. Based upon these findings, it appears that EC housing is better for the health and welfare of egg-laying chickens than CC or AV housing.

Effects of a new anatomical adaptive titanium mesh cage on supportive load at the cervical endplate: a morphological and biomechanical study

To assess the geometrical matching of a new anatomical adaptive titanium mesh cage (AA-TMC) with the endplate and its effect on cervical segmental alignment reconstruction in single- and two-level anterior cervical corpectomy and fusion (ACCF) and compare the compressive load at the endplate between the AA-TMC and the conventional titanium mesh cage (TMC). Twelve cervical cadaveric specimens were used to perform single- and two-level ACCF. The interbody angle (IBA), interbody height (IBH) and the interval between the AA-TMC and the endplate were evaluated by comparison of the pre- and postoperative X-ray images. The maximum load at the endplate was compared between the AA-TMC and TMC based on American Society for Testing and Materials (ASTM) F2267 standard. No significant differences were found between the preoperative and postoperative IBA and IBH in either single-level ACCF (11.62°±2.67° vs 12.13°±0.69° and 23.90±2.18 mm vs 24.23±1.13 mm, respectively; P &gt; 0.05) or two-level ACCF (15.63°±5.06° vs 16.16°±1.05°and 42.93±3.51 mm vs 43.04±1.70 mm, respectively; P &gt; 0.05). The mean interval between the AA-TMC and the endplate was 0.37 ± 0.3 mm. Compared to the conventional TMC, the use of AA-TMC significantly increased the maximum load at the endplate in both single-level ACCF (719.7±5.5 N vs 875.8±5.2 N, P &lt; 0.05) and two-level ACCF (634.3±5.9 N vs 873±6.1 N, P &lt; 0.05). The use of AA-TMC in single-level and two-level ACCF can significantly increase the maximum load at the endplate to lower the possibility of implant subsidence and allows effective reconstruction of the cervical alignment.

INFLUENCE OF PEN HOUSING WITH LITTER ON SANITARY STATUS, PERFORMANCE AND CARCASS TRAITS OF GROWING RABBITS

The objective of this study was to evaluate the health status, productive performance and carcass traits of growing rabbits housed in pen with litter and conventional cage. At 35 d, 54 crossbred rabbits (New Zealand White vs. Botucatu) were randomly housed in pen with litter (6 pens, 6 rabbits/pen, 2.3 rabbits/m²) or cage (6 cages, 3 rabbits/cage, 8.3 rabbits/m²) and kept until the age of slaughter at 77 d. To simulate farm conditions, the rabbits that were housed in pen have not been previously adapted to this system. There was greater intensity of dirt and mucus occurrence in the rabbits housed in pens in first period, but the mucus occurrence practically disappeared in the later period. For performance, the rabbits housed in cages had a higher live weight at 56 d (1714 vs. 1506 g; P 0.05) in the posterior period (56 to 77 d). There was no effect (P>0.05) of housing system for carcass yield, dissectible fat and hind leg yield. It may be suggested that rabbits adapt to the floor over time. Therefore, it is indicated the adoption of this system for growing rabbits.

Laboratory animal allergy is preventable in modern research facilities.

Historical data suggest 15% of laboratory animal workers develop IgE sensitisation and 10% symptoms of laboratory animal allergy (LAA), including occupational asthma. Individually ventilated cages (IVCs) are replacing conventional open cages; we sought to evaluate their impact on the development of LAA. We surveyed 750 laboratory animal workers and measured airborne Mus m 1 (mouse allergen) levels in seven UK institutions. We compared the prevalence of sensitisation to mouse proteins (by specific IgE assay or skin prick test) and of work-related allergic symptoms in IVC-only and open cage units. Full-shift Mus m 1 levels were lower in IVC than open cage units (geometric mean 1.00 (95% CI 0.73-1.36) versus 8.35 (95% CI 6.97-9.95) ng·m-3; p<0.001), but varied eight-fold across the IVC units (geometric mean range 0.33-4.12 ng·m-3). Primary analyses on data from 216 participants with ≤3 years exposure to mice revealed a lower prevalence of sensitisation in those working in IVC units compared with conventional cage units (2.4% (n=2) versus 9.8% (n=13); p=0.052). Sensitisation in IVC units varied from 0% to 12.5%; the use of fitted respiratory protection was less common in IVC units where prevalence of sensitisation was higher. Work-related allergy symptoms were more frequently reported by mouse-sensitised individuals (46.7% versus 10.9%; p<0.001) and only by those working in open cage units. In contemporary practice, LAA is now largely preventable with the use of IVC systems and the judicious use of appropriate respiratory protection.

Colonization of internal organs by Salmonella Enteritidis in experimentally infected laying hens of four commercial genetic lines in conventional cages and enriched colony housing

The prevalence of Salmonella Enteritidis in commercial egg-laying flocks is a prominent public health concern because contaminated eggs cause human illness. Deposition of this pathogen inside eggs results from bacterial colonization of reproductive tissues in infected hens. Environmental conditions can influence avian Salmonella infections, but the food safety consequences of different poultry housing systems remain uncertain. The present study assessed the invasion of internal organs by Salmonella Enteritidis in groups of experimentally infected laying hens of four commercial genetic lines (designated as white egg lines W1 and W2 and brown egg lines B1 and B2). Groups of hens from each line were housed at 555 cm2 of floor space per bird in both conventional cages and colony units enriched with access to perches and nesting areas. All hens were orally inoculated with 5.75 × 107 colony-forming units of a two-strain Salmonella Enteritidis mixture. At 6 to 7 d post-inoculation, hens were euthanized, and samples of liver, spleen, ovary, oviduct, and intestinal tract were removed for bacteriologic culturing. The frequency of Salmonella Enteritidis recovery from intestinal samples was significantly (P < 0.05) greater for the two white egg lines combined than for the two brown egg lines combined in both conventional cage (72.2% vs. 50.0%) and enriched colony housing systems (66.7% vs. 37.5%). The frequency of intestinal Salmonella Enteritidis isolation from line B1 was significantly higher from hens in conventional cages (47.2%) than in enriched colonies (22.2%), but no differences were observed for other hen lines. Line W1 yielded more positive intestinal samples than either brown egg line in conventional cages, and line B2 had fewer positive intestinal samples than all other lines in enriched colonies. There were no significant differences between hen lines or housing systems in Salmonella Enteritidis isolation from other internal organs. These results demonstrate that Salmonella Enteritidis colonization of the intestinal tract can vary between genetic lines of egg-laying hens and that some lines are subject to housing system influences on Salmonella susceptibility.

Feeding high-oleic peanuts to layer hens enhances egg yolk color and oleic fatty acid content in shell eggs

Previous studies have identified normal-oleic peanuts as a suitable and economical broiler feed ingredient. However, no studies to date have examined the use of high-oleic (HO) peanut cultivars as a feed ingredient for laying hens and determined the impact of feeding HO peanuts on performance and egg nutritive qualities. This project aimed to examine the use of HO peanuts as a feed ingredient for layer hens to determine the effect on performance, egg lipid chemistry, and quality of the eggs produced. Forty-eight 40-wk-old layer hens were fed a conventional soybean meal + corn control diet or a HO peanut + corn diet for 10 wk in conventional battery cages. Body and feed weights were collected weekly. Pooled egg samples were analyzed for quality, lipid analysis, and peanut protein allergenicity. There were no significant differences in hen performance or egg quality as measured by USDA grade quality, egg albumen height, or egg Haugh unit between the treatment groups. However, eggs produced from layer hens fed the HO peanut + corn diet had reduced egg weights relative to the controls (P = 0.0001). Eggs produced from layer hens fed the HO peanut diet had greater yolk color scores (P < 0.0001), HO fatty acid (P < 0.0001), and β-carotene (P < 0.0001) levels in comparison to the controls. Eggs produced from hens fed the control diet had greater palmitic and stearic saturated fatty acids (P < 0.0001), and trans fat (P < 0.0001) content compared to eggs produced from hens fed the HO peanut diet. All egg protein extracts from all treatments at each time point were non-reactive with rabbit anti-peanut agglutinin antibodies. This study identifies HO peanuts as an abundant commodity that could be used to support local agricultural markets of peanuts and poultry within the southeastern United States and be of economic advantage to producers while providing a potential health benefit to the consumer with improved egg nutrition.